Book Description
This is a full-length study of Wittgenstein's third masterpiece. It unravels Wittgenstein's ultimate and highly-consended thoughts on knowledge, certainty and scepticism. The author elucidates Wittgenstein's view of basic beliefs as animal certainties — that is, as nonreflective, nonpropositional attitudes whose verbal articulation is, at best, heuristic. What philosophers like Descartes and Moore have put forward as propositions susceptible of falsification, and therefore vulnerable to scepticism, are nothing but heuristic formulations of certainties whose only occurrence qua certainty is in action.

Brief Description
In this paper, I take issue with Pieranna Garavaso's contention – lodged in a rapprochement between Wittgenstein and Quine – that for Wittgenstein, there is no sharp categorial distinction between logical and empirical propositions, but only one of degree. I argue that Garavaso's conclusion results from a misunderstanding of the river-bed analogy in On Certainty (96-99). When Wittgenstein maintains there is not a sharp boundary between propositions of logic and empirical propositions, he does not imply that there is not a sharp categorial difference between them, but that the boundary is permeable. The consequent changeability of status of logical and empirical propositions does not entail the collapse, or even a partial blurring, of their respective categories. I then address Wittgenstein’s puzzlement, in On Certainty, about the logical status of some apparently empirical propositions, and show that he resolves this not, as is often thought, by concluding that some empirical propositions are necessary, but by recognizing the 'empiricality' of these propositions as merely apparent. A line is thereby drawn between empirical propositions and framework propositions that only have the form of empirical propositions (OC 401). I conclude that, unlike Quine, Wittgenstein held a foundational view of our system of beliefs, making a categorial distinction between the foundation-walls and the house, and regarding part of these foundations as immovable.

Brief Description
'Hinge propositions', Wittgenstein's version of our basic beliefs, are not propositions at all, but heuristic expressions of our bounds of sense which, as such, cannot meaningfully be said but only show themselves in what we say and do. Yet if our foundational certainty is necessarily an ineffable, enacted certainty, any challenge of it must also be enacted. Philosophical scepticism – being a mere mouthing of doubt – is impotent to unsettle a certainty whose salient conceptual feature is that it is lived. I appeal to psychopathology to show that the lived refutation of a basic certainty is not a manifestation of uncertainty, but of madness.

Rudd, Anthony, 'Wittgenstein, Global Scepticism and the Primacy of
Practice' in Readings of Wittgenstein’s On Certainty eds. D.
Moyal-Sharrock and W. Brenner (Palgrave, London and Basingstoke, 2005)
142-161.

Brief Description
I define global scepticism as a doubt, not about particular empirical facts, but about the ultimate ontological status of such facts. Although Wittgenstein says relatively little about this in On Certainty, that little does suggest an argument based on the fundamental principle of his later thought, the association of meaning and use. If the dispute between e.g. realists and idealists about the ultimate ontological status of things is not manifestable in practice, then it is empty – and so therefore is the claim of the global sceptic that we must suspend judgment between such rival analyses. I then argue that this argument is, as it stands, inadequate in two ways. Firstly, it underestimates the flexibility of usage; and secondly, it appears to presuppose an idea of the primacy of practice, which is itself a philosophical thesis of some kind. But this seems to beg the question against the sceptic, and to conflict with the supposedly anti-theoretical thrust of Wittgenstein’s own philosophy. I argue that the idea of the primacy of practice can be defended, but that this requires a commitment to an essentially Kantian transcendentalism which Wittgenstein is unwilling to do more than hint at. This, however, needs to be more fully articulated before we can come to a conclusion about the success of his case against scepticism.

Brief Description
This paper examines the relevance of Wittgenstein's On Certainty to the contemporary debate regarding the problem of radical scepticism. In particular, it considers two accounts in the recent literature which have seen in Wittgenstein's remarks on 'hinge propositions' in On Certainty as the basis for a primarily epistemological anti-sceptical thesis viz., the inferential contextualism offered by Michael Williams and the 'unearned warrant' thesis defended by Crispin Wright. Both positions are shown to be problematic, both as interpretations of Wittgenstein and as anti-sceptical theses. Indeed, it is argued that on a reading of On Certainty which has Wittgenstein advancing a primarily epistemological thesis, there is in fact strong evidence to suggest that Wittgenstein thought that no epistemic response to the sceptic was available at best, it seems, only a pragmatic anti-sceptical thesis is on offer. Such a conclusion is not without import to the present debate regarding? radical scepticism, however, since it poses a general challenge for how the sceptical argument is? conceived in the contemporary literature.
[Available at: http://www.philosophy.ed.ac.uk/new/staff/fullacademic/documents/WittgensteinianEpistemology_000.pdf]

Brief Description
A certain interpretation of Wittgenstein's remarks in On Certainty advanced by such figures as Hilary Putnam, Peter Strawson, Avrum Stroll and Crispin Wright has become common currency in the recent literature. In particular, this reading focuses upon the supposed anti-sceptical import of the Wittgensteinian notion of a 'hinge' proposition. In this paper it is argued that this interpretation is flawed both on the grounds that there is insufficient textual support for this reading and? that, in any case, it leads to unpalatable philosophical problems. Moreover, it is claimed that the popularity of this construal of On Certainty in the contemporary debate reflects an implicit commitment to the contentious doctrine of epistemological internalism. Nevertheless, it is argued that, suitably modified along the epistemologically externalist lines suggested by Michael Williams, one might be able to resurrect a viable anti-sceptical hinge proposition thesis. Furthermore, it is claimed that such a conception of the notion also receives some, albeit inconclusive, textual support from On Certainty.
[Available at: http://www.philosophy.ed.ac.uk/new/staff/full-academic/documents/ScepticismExternalismHPs.pdf]

In this paper Peter Klein's criticism of Wittgenstein in "Certainty: A Refutation of Scepticism" is addressed. Klein claims that, according to Wittgenstein, we attribute knowledge of a proposition p to a person only if that person is not certain of p. I argue that a careful reading of Wittgenstein's On Certainty reveals that there are two kinds of objective certainty that Wittgenstein had in mind; propositional objective certainty and normative objective certainty. Klein fails to distinguish between the two and uses what I call propositional objective certainty to make his point against Wittgenstein. I claim that when Wittgenstein said that knowledge and certainty belong to different categories he was talking of normative objective certainty and, therefore, that Klein's criticism is misplaced and attributes to Wittgenstein a position that is not his.